1. Field
This disclosure relates generally to memories, and more specifically, to memories with enhanced sensing speed.
2. Related Art
It is a common desire for memories to have a fast sensing time. The increase in speed, which is reflected in reduced sensing times in a memory is partly facilitated by faster transistors achieved with smaller dimensions such as reduced channel lengths. Achieving faster transistors in this manner, however, also results in transistors with lower breakdown voltages. This in one reason that there has been a trend in integrated circuits to reduce the voltage of the power supply. The lower power supply voltage has the affect of reducing gate voltages and thus reducing the magnitude of the gate to source voltages. The magnitude of the gate to source voltage directly effects the degree of conductivity of the transistors which in turn can reduce speed because it is typical for input capacitances to be a significant factor in speed. Thus the degree of conductivity directly effects the speed with which a capacitive input can be changed. Threshold voltages have been lowered to only a 2 to three tenths of a volt or even lower, which leaves little room for improvement in increasing the magnitude of gate to source voltages by decreasing the threshold voltage.
Thus, there is a need to improve the speed of sensing in memories in light of the reducing power supply voltages commonly used for the high speed transistors.